If you’re looking for some good news, how about this: Researchers are seeing no signs of the red tide algae blooming anywhere in the Gulf.
The toxic red tide algae — Karenia brevis — occurs naturally in the Gulf of Mexico in low concentrations. Natural background levels of red tide are 1,000 cells or fewer, per liter of water. Higher concentrations can prove toxic.
It is a little early in the year for it, but Florida Fish and Wildlife Conservation Commission’s interactive map on myfwc.com shows no signs of the algae blooming anywhere along Florida’s coasts.
“Red tide research and monitoring scientists are not seeing any indications of a bloom (or developing bloom) of the red tide algae Karenia brevis,” FWC spokeswoman Michelle Kerr said Monday.
“This lack of cells is somewhat expected, simply because it is not the time of year where we typically see a lot of red tide,” Kerr said “It’s not unheard of, but if we were to see anything develop right now, it would certainly be early relative to the majority of blooms.”
Higher concentrations of red tide can cause fish kills, closures of shellfish harvesting and respiratory irritations and other physical ailment in humans when concentrations exceed 100,000 cells or more per liter of water. Winds and currents drive red tide ashore. Toxins generally are released when the delicate algal cells break up due to wave action.
Two years ago, Southwest Florida experienced 15 consecutive months of intense and sustained red tide blooms hugging the Gulf coastline that began in late June, 2018. The red tide blooms not only resulted in massive fish kills, but also led to the deaths of adult sea turtles, dolphins and other sea life. The FWC has limited the recreational fishing seasons for snook, redfish and sea trout to catch-and-release to give time for the fish to replenish from what was lost to that red tide bloom.
Red tide blooms
According to Ocean Circulation Group, University of South Florida College of Marine Science and other researchers, red tide first thrives well offshore in low-nutrient waters in the middle of the Gulf’s continental shelf. Deeper ocean currents can influence the Gulf shelf with an upwelling of deeper water that carries nutrients.
“If this occurs in spring to summer months, when (red tide) blooms tend to form offshore, other faster-growing microscopic plants can prevail over the slower growing (red tide), suppressing red tide bloom development,” a summary of the research states on myfwc.com.
As part of a cooperative research effort, the FWC, USF and Mote Marine Laboratory are undertaking a monitoring effort of the Gulf for red tide.
“USF’s glider is still in the water, so we can track what’s going on in near real time,” Kerr said.
According to the FWC, red tide cells, once present, can be transported toward or away from the coast depending on currents and winds — which often intensify during storms.
“These and other factors generally make it difficult to predict what might happen,” Kerr said.
While red tide is able to thrive under a wide range of environmental conditions, it cannot grow in low salinity of brackish water or flushes of fresh water.
To learn more about red tide, visit myfwc.com.